Lower-case as key would slower, and why?

[Jakit Liang]

```

local start

-- Faster

local t1 = {x = 0, y = 0}

start = os.clock() for 1, 50000000 do t1.x = t1.x + 1 t1.y = t1.y + 1 end

print(os.clock() - start) -- Slower local t2 = {X = 0, Y = 0}

start = os.clock()   for 1, 50000000   do t2.X = t2.X + 1 t2.Y = t2.Y + 1 end
print(os.clock() - start)

```

In this case, why the second one runs slower?

[Sainan]

Both execute well within margin of error within each other for me, if anything the second loop runs faster because the CPU is warmed up by then...

Anyway, too many factors of other programs running, thermals, CPU utilisation, the universe's background radiation, what Zeus ate for breakfast today... don't try to optimise on such a trivial detail. The biggest gains are from using better/faster algorithms.

-- Sainan

[blog...@gmail.com]

The difference is at the level of error, the first test is normal, the second cycles have swapped places.

```

cat test.lua ; alua test.lua ; cat swap_tests.lua ; alua swap_tests.lua

local t1 = {x = 0, y = 0}

local t2 = {X = 0, Y = 0}

start = os.clock() for i = 1, 50000000 do t1.x = t1.x + 1 t1.y = t1.y + 1 end
print(os.clock() - start)
start = os.clock() for i = 1, 50000000 do t2.X = t2.X + 1 t2.Y = t2.Y + 1 end
print(os.clock() - start)
☺─────────── luajit ────────────☺
0.075292
0.063305
☺─────────── lua5.1 ────────────☺
4.589889
4.608593
☺─────────── lua5.2 ────────────☺
4.537976
4.585994
☺─────────── lua5.3 ────────────☺
3.79108
3.852186
☺─────────── lua5.4 ────────────☺
3.17556
3.153118

☺─────────── lua5.5 ────────────☺

2.996931
3.008384

local t1 = {x = 0, y = 0}

local t2 = {X = 0, Y = 0}

start = os.clock() for i = 1, 50000000 do t2.X = t2.X + 1 t2.Y = t2.Y + 1 end
print(os.clock() - start)
start = os.clock() for i = 1, 50000000 do t1.x = t1.x + 1 t1.y = t1.y + 1 end
print(os.clock() - start)

☺─────────── luajit ────────────☺
0.070102
0.066586
☺─────────── lua5.1 ────────────☺
4.773055
4.861655
☺─────────── lua5.2 ────────────☺
4.388561
4.395681
☺─────────── lua5.3 ────────────☺
3.605546
3.91049
☺─────────── lua5.4 ────────────☺
2.996931
3.008384

☺─────────── lua5.5 ────────────☺

4.366968
4.363553

```

If you disable garbage collection, the values are about the same. I have a dynamic processor frequency, I ran tests 4 times, the difference for the same case is 0.5 seconds, depending on the frequency and load of the processor. In short, I do not see a correlation between speed and UP/low

воскресенье, 20 июля 2025 г. в 18:03:34 UTC+3, Sainan:

[Jakit Liang]

Thanks for your testing result! It is useful for me.